1. Field of the Invention
The present invention relates to a pipette tip transport and loading system.
2. Description of the Related Art
Pipette tips are widely used in chemistry, biomedical and bioengineering testing for transporting and dispensing discrete amounts of a liquid sample. A typical pipette tip is made of plastic and formed with a substantially conical head and a frustoconical body. In most applications, pipette tips are used in large quantities, making individual handling of the pipette tips highly inconvenient. Consequently, pipette tips are typically loaded into pipette tip platforms so that the user need not handle the pipette tips individually. By utilizing platform loading, liquid samples can be efficiently stored and transported in large quantities.
Platforms of pipette tips are often stacked and packaged one atop the other. For example, refill packs are sold including a tower of stacked platforms, packaged within a housing. Typically, some sort of device is used to transfer platforms from the stack and to deposit a platform into a pipette tip rack, one platform per rack. Standard pipette tip racks and platforms typically have a rectangular upper surface which defines an array of apertures. In a rack, liquid samples may be transferred to and/or from pipette tips in the rack from an array of pipettors.
A number of devices have been developed that facilitate unloading pipette tip platforms from a stack of pipette tip platforms. U.S. Pat. Nos. 5,392,914, 5,441,702, 5,612,000 and 6,007,779 to Lemieux et al., and U.S. Pat. No. 5,779,984 to Kelly et al. each describe refill packs for pipette tip racks. The refill packs described in those patents enclose stacks of pipette tip platforms in a box-like packaging having an open lower end from which the pipette tips in the lowest platform in the stack extend. The packaging is grasped by the user and the pipette tips in the lowermost platform are manually fitted into a pipette tip rack. The pipette tip platforms are held within the rack by a flange extending around the perimeter of the open end of the refill pack. When the packaging is pressed downwardly, the flange is deformed outwardly by the downward force exerted by the lowermost pipette tip platform, and the platform is forced through the flange and remains on the rack. Once the platform has passed through the flange, the flange elastically returns to its original position, retaining the rest of the pipette tip platforms within the packaging.
There exists a continuing need for alternative, reusable loading devices which can dispense units of platform-loaded goods in a single dispensing action, and can be simply and reliably operated.